A disadvantage of known closures is that the cover portion must be made of relatively hard, and usually also brittle, synthetic material, since grasping and rotating the cover portion in the region of the jacket leads to lateral compression of the jacket portion. Deformation of the jacket portion must be avoided in view of the functional capacity of the run-up protuberances. In addition, the fact that the foot portion must be elastic with a view to subsequently fitting the closure to a container, means that the cylindrical pouring portion is also elastic and accordingly is not capable of holding the cover portion securely in position. This involves considerable difficulties if the cover portion is intended to be linked to the foot portion by a guarantee ring, since the guarantee ring may be damaged if the two parts undergo mutual lateral displacement.
The present invention has for an object to avoid the disadvantages of known closures, and in particular to provide a pourer closure which can be rationally produced and which may be provided with a damage-proof guarantee ring.